Understanding Adolescence: Changes and Challenges

Today we're talking about adolescence. Probably, in my opinion, one of the more interesting time periods to talk about. Very tumultuous time and development as I'm sure you all remember fondly. So adolescence runs maybe a little bit later than you would think. So it goes from 12 until at least 19 and some researchers even count adolescence up until about like 21 because there's some pretty interesting brain developments happening up until like early 20s. So I would say definitely 12 to 19, maybe up to 21-ish is the age range we're talking about here. So if we're talking about physical changes in adolescence, you can probably assume that puberty is going to be a huge part of that. So puberty leads to all kinds of really dramatic changes in our physical appearance, and it also impacts the brain in really significant ways that we'll talk about. And then in the next PowerPoint, we'll also talk about how puberty affects our emotions and social interactions. Because of some of the changes in the brain, adolescents are much more prone than other time periods to engage in some really risky behaviors. So we'll talk a little bit about some of the brain changes that contribute to that. And then we'll also talk about some cognitive developments in things like reasoning abilities and scientific understanding. So that's the plan for today. So let's start with puberty. So kind of the main thing that's driving a lot of the changes that you experience during puberty are in hormonal changes. So, you know, all genders have some growth hormones that are contributing to overall physical growth. The main ones are thyroxine, and then there's also a hormone that's literally just called growth hormone. So growth hormone and thyroxine are the two. Biggest hormones that are contributing to just like overall growth where you get another growth spurt around this time around puberty. And then in addition to those there are also what we call the sex hormones. And sex hormones tend to differ based on gender. So the two biggest groups of sex hormones are androgens and estrogens. Androgens would include things like testosterone for example is the biggest one. Androgens tend to be more active in cisgender boys and then estrogens are more active in cisgendered girls Although all genders have a little bit of each of those there's like this imbalance between the genders So the androgens again that would be like testosterone they tend to contribute to like hair growth all over the body They contribute to the growth spurts that cis boys experience during this time and particular to the development of muscles and they also increase metabolism and tend to like broaden the shoulders and then the Estrogens that would include estrogen and progesterone are the two big Estrogen sex hormones again. They tend to be more active in cisgendered girls. They're gonna stimulate like growth of the breast tissue They help with maturation of the you know genitals and females vagina. They also contribute to like fat storage in particular areas. So cis girls tend to, you know, develop fat mostly in like the thighs and the hips. And then importantly those estrogens also trigger the menstrual cycle. So these hormonal changes are going to contribute to a lot of the primary and secondary sexual characteristics. So primary sexual characteristics are basically the genitals. And then secondary sex characteristics are the things that we can mostly see. So things that are visible like, you know, largening of the breasts, growth of facial hair, etc. There tend to be pretty large individual differences in the onset of puberty. So it can happen as early as like 9 or 10 in some cases. And then as late as, you know, 14 or 15. It's a pretty normal range for the start of puberty. And those differences can actually impact the genders in different ways. So there's pretty good evidence that girls who are early bloomers, like girls who have puberty earlier, tend to have worse outcomes than girls who are late bloomers. So girls who are early bloomers, they tend to have issues with like self-esteem and self-confidence. They tend to be much more uncomfortable physically in their body. They also tend to be like bullied and ostracized more. For boys, it's basically the opposite. So boys who tend to be early bloomers if they start puberty earlier They're gonna grow to a taller height sooner. They're gonna, you know build up muscle sooner And so they tend to have better social outcomes compared to boys who tend to be late bloomers So you have a boy that hasn't gone through puberty until fairly late then they're much more likely to be ostracized or bullied Also, kind of interesting note, age of puberty onset has been decreasing for some reason since the early 1900s. Like overall as a whole population, we tend to start puberty earlier now compared to then. Part of that might actually be a healthy thing. So in the early 1900s, more people were more likely to be suffering from like malnutrition. And we know that things like malnutrition can actually delay the onset of puberty. So that might be part of that reason for puberty onset. age decreasing now because we have much more access to you know better health outcomes better nutrition etc another thing I want to talk about a little bit really quickly is the use of puberty blockers during this age it's kind of a controversial subject for some people but puberty blockers are usually used they're used for a lot of context but the part that's controversial is when they're used for someone who's transitioning from their birth gender to their gender identity And basically what puberty blockers do, I mean it's in the name, they're like a medication you take that basically stops the hormones, the sex hormones, from being produced as much. And so it will temporarily stop puberty. So it'll stop a lot of the processes that we just talked about. Someone who takes puberty blockers, they can basically stop taking them at any point and then their puberty would resume just like normal, like it would have if they had never stopped or started taking the puberty blockers. So kind of the idea is that like let's say for example you have someone who's born a female and they want to transition to male Whenever they start to go through puberty their body's going to start pumping out all these estrogens that might start to cause you know breast Growth etc. And if they want to transition to male they identify as male that's going to make them extremely uncomfortable likely So these puberty blockers would stop that process. It would basically shut down the body pumping out that estrogen So they would kind of remain in this like pre-puberty state for a little bit. Some people choose to do that basically to delay puberty so that they have more time to make decisions. So if it's you know, most the time if someone's transitioning, they're pretty much 100% certain that's what they want to do. But if for some reason they're a little bit on the fence, they think they want to transition, they're not really sure, then those puberty blockers kind of stop them from developing these sexual characteristics for a little bit. So they have more time to think about it and decide. Yeah, Ashley. Yeah, that would be a part of that. So puberty blockers basically would stop that sexual maturation process. And then most people, the huge majority of people, if they are transitioning and they take the puberty blockers, then they will eventually follow that up by doing hormone replacement therapy or hormone replacement therapy using... the sex hormone of the gender they're trying to transition to. Right? So again, if you have someone who's born female but they want to transition to male, they might take the puberty blockers to stop the growth of breasts and all of that and then eventually they'll take the testosterone in order to basically start developing like male sexual characteristics. Yeah? Is it one of the drugs, I forget the name of it, but wasn't it used to like chemically castrate offenders? I don't know. I've never heard that. But that would, I mean, I could imagine that if, like, for example, if there's one that blocks testosterone, if you took it in a high enough dose, then it might, yeah, stop the production of testosterone, which would shut down sperm production. So that's possible. I've never heard that, though. I mean, shutting down any production is going to kill someone's sex drive. Yeah. I think no matter what. Right. Yeah. Yeah, it's possible. I mean, they say it doesn't happen on, like, hormonal birth control, but it totally does. Yeah, definitely. Yeah, there's all kinds of effects of hormonal birth control that are not taken as seriously as they should be, probably. Essentially, so yeah, so if you have, let's see, the opposite, right? You have someone who's born male, they want to transition to female, then they would take the puberty blockers, and then later on they would supplement with estrogens, which would be, yes. Yeah, yeah, so yeah. birth control would have very similar effects and would fall in the same kind of category. So some of the controversy or the criticisms of puberty blockers, one is fairly valid, which is that puberty blockers tend to decrease bone density. So another thing that these sexual hormones do is that they help strengthen and grow the bones. And so if you're blocking... The, you know, puberty, if you're blocking those hormones during puberty, even if someone then starts taking the hormone supplements later or they stop taking puberty blockers, they still aren't going to develop the same bone density as someone who's just allowed to go through puberty naturally. Yeah. Does it affect long-term fertility? I would imagine so. I haven't, I don't remember reading that directly, but yeah, I would imagine that it probably would. Yeah, so there are side effects, but I mean obviously there's side effects to all kinds of medications and people make decisions based on mitigating risk and weighing benefits, etc. Another common criticism you hear that's much less valid is the concern that, you know, what if someone changes their mind? So kind of the idea is that if you have someone who's 12, you know, are they able to make a lifelong decision that they're not going to regret? And if they do take these puberty blockers and start transitioning and then they get to 18 and they decide like oh This was a bad choice, then you know that might have negative outcomes However, you know statistically about 99% of people who choose to take puberty blockers are happy with that decision in adulthood 98% of them will go on to do other transitional therapies, so if they start taking the puberty blockers It's very very high chance that they will follow through with the hormone replacement therapy, and in a lot of cases also might follow through with, like, surgeries. Yeah? I heard of this other study. It was a long time ago, and I can't remember the name of the guy, but I think he was Canadian. And he did a, I think it was a longitudinal study on adolescents who had gender dysphoria. Yep. I feel like crap that I can't even, I didn't remember the name of it, but he said that a majority of the children that he studied ended up by the age of 18 just detransitioning, I suppose. I think he ended up like losing his license for it. Interesting. Yeah. Yeah. Canadian. You know, he chose his Canadians. Right, yeah. Yeah, I mean most of the studies I've read, like I said, say that 99% of the children are Canadian. of them end up being happy with it. Yeah, that's what I'm wondering. Maybe in that particular case, he was pressuring people to do it or something for some reason. I mean, who knows? Yeah, and also just to put that into context, so if 99% are happy with it, with it, that means about 1% end up regretting the decision. About 1.2% of people regret getting LASIK eye surgery because it has long-term side effects, can have dry eyes and stuff. So pretty much any medical procedure you can think of, of course, there's going to be people who end up regretting doing that procedure because there's complications or things that they didn't think through. So that's often one of the arguments that's used to say we shouldn't let people use puberty blockers. In my opinion, it's not a very great argument against. So kind of like I think we talked about this last time, this idea that if you have someone in late childhood who's expressing, you know, wanting to transition, then it's good to support that. Same thing here in general if an adolescent someone is wanting to transition genders, all the evidence suggests that the best outcomes are going to come from supporting that decision. And if they're not supported, that can often lead to you know, depression, anxiety, suicidal thoughts and tendencies. So really negative outcomes if you don't try to accept their transition. Yeah? I also read somewhere that it's like a really astronomical number of people who are transitioning or have transitioned that they have like an attempted suicide rate that's really high too. Yeah. It seems like it's just being all around. Yeah, I would imagine that being in that transitionary phase is probably the most difficult part, right? Because you're... I'm sure most people are very uncomfortable in the body of their born gender, but then being in that transition, you're kind of like halfway in between and not really comfortable. But then people who go through the full transition and come out the other side tend to have much better outcomes. All right, so I've got to say about puberty for now. We might talk about it a little bit more in the context of emotional and social development. Well, it's not all I have to say about it. It's all I have to say about the sexual changes from puberty, at least. Puberty... contributes pretty significantly to some drastic changes in brain development. So a couple things to note, up until early 20s the prefrontal cortex is still not fully developed. So even for some of you in this classroom, you know, depending on your age you might not have a fully developed prefrontal cortex yet. And that is the part of the brain that's involved in executive control, which we've talked about multiple times, you know, that ability to plan, set goals, self-regulate, etc. So that won't be fully developed, like I said, until about early 20s. Most of the development that's going on physically is myelination and pruning. So you've got pretty much all the neurons in place at that point, but the myelin is not fully developed. And again, myelin is the part that sort of speeds up those connections in the brain. So during adolescence, you're still having some of that development happening. Prefrontal cortex is continuing to develop. So executive control is getting better, but it's still not at its peak that it will be in early 20s. Maybe more importantly, there's also some pretty drastic changes going on in the reward network of the brain. So the reward network is a system of structures that is active whenever we do something pleasurable, basically. So this would involve like dopamine. If you've ever heard of dopamine, this whole idea of, you know, lots of things that are addictive tend to trigger dopamine activity. That's the neurotransmitter that's used in this particular network. And in adolescence, there are some really interesting things happening in that network that basically make it so that adolescents, when they're making a decision, they tend to weigh the rewards of an outcome way more. And they tend to discount the risks or the possible, you know, negative outcomes of that decision. So if you have a teenager who's, you know, with their friends and their friends are asking them to drink or use drugs or whatever, and they're making a decision about whether or not to do that, they're going to focus a lot on the reward. They're going to focus on, OK, this is going to be fun. It's going to feel good. My friends are going to think I'm cool, et cetera. And they're not going to think about the possible negative consequences of that because of like literal. neurological, physical changes in the brain that kind of make them think that way, basically. So we're going to talk a little bit about risky behaviors that teenagers engage in. And I guess kind of the main thing I want you to think about now is that that's completely normal and sort of built into our brains to act that way during adolescence. So in addition, I mean, I kind of, this is more relates to... the prefrontal cortex stuff I was talking about, you've also got some synaptic pruning still going on in some areas and expansion in the others. So, you know, expansion is mostly happening in the prefrontal cortex. So yeah, so continued changes in brain development, basically. All right, some other physical changes that are happening in adolescents have to do with the sleep-wake cycle. And again, this is... partially due to changes in the brain and also changes in those hormones that we've already talked about. And those changes sort of combine to lead to later sleep onset and also to the need for more sleep compared to early and middle childhood. So in an ideal setting, adolescents would basically be allowed to go to sleep later and sleep for longer than they did in childhood. Unfortunately our society isn't really set up to support that although there are some initiatives to try to change that. So in the past decade or so I've seen all kinds of states trying to implement rules for like you know starting high schools later and setting rules about how early they can start and having like thresholds on that. So yeah so but because of these changes and sort of come yeah go ahead Valerie. her kid being on an opposite schedule was a really big pain in the ass to her. And there was no other way to get, I think it was pre-COVID too, so there wasn't like online classes there. But it was a big pain in the ass and it made me think about that. Like there are a lot of adults who are on a nighttime schedule. It's just not, I don't know. My husband was on the night schedule for a long time, you know, in the military. It was rough. Yeah, yeah, it's very, yeah, yeah, definitely. It's extremely difficult. And yeah, and I mean, even. you know, outside of that, like I'm saying, like pretty much all of society is set up to run from nine to five or whatever. And our school systems run mostly from, you know, eight to three-ish. And yeah, it's just not really conducive to the development of adolescence. So yeah, so because of that, adolescents are chronically sleepy, basically, as I'm sure all of you are aware and probably feeling right this moment. And lack of sleep leads to all kinds of negative outcomes. It impairs executive function, which is already not... fully developed, so then that's going to contribute, again, to some of those risky behaviors. Impaired emotional regulation, also reduced achievement in school, increased anxiety and depression, and then all of that sort of combines to some of the high-risk behaviors we'll talk about in a little bit. Also, I should point out, too, that lack of sleep has all kinds of physical negative outcomes. It can reduce our immune function, so we're more likely to get sick. It also has really negative impacts on the brain if you're not sleeping enough or sleeping deeply enough There's pretty good evidence that chronic lack of sleep might increase your risk for Alzheimer's and dementia Partially because so while you're sleeping your brain is actually flushing a lot of like waste material And if you're not getting enough sleep, then you're not going through that process and those waste materials sort of build up and cause declines in the neurons, basically, that can lead to, like I said, Alzheimer's and dementia. So it's a really important issue. Does it have any effect on the physical growth, too? Because that's... Yes, yeah, I mean, that's another thing that's happening while you're sleeping. Your body's repairing, recovering from exercise or any other sort of damage, and also, yeah, contributing to growth. So, yeah, lack of sleep is going to impair all of that. Alright, teens also tend to have somewhat poor nutrition compared to some of the other age ranges we've talked about. And part of that is due to the fact that calorie requirements increase. So when you're going through puberty, you know, all this growth is happening. You know, also high schoolers often very likely to participate in like extracurricular activities, sports and physical education and all of that. So they need more calories, but they often are on a time crunch. Again, I always feel kind of silly talking about adolescence. It's like my favorite, most interesting time period. But saying all this to all of you who are mostly in adolescence feels so silly to me. Like, you know this because you're living it every single day. So adolescents tend to be on a pretty big time crunch. They're going to school. They've got extracurriculars. A lot of people start working during this time period. And so trying to find time to eat even remotely healthy is very difficult. So adolescents are more likely than any other time period to eat on the go. So eating fast food or just grabbing like you know a granola bar or something to eat for breakfast. In addition to that around this age is when eating disorders become most common particularly in girls. So all of that can lead to poor nutritional outcomes. You've got adolescents whose brains aren't fully developed, not getting enough sleep, they're not eating great. Yeah, did you have a question? So we're talking 12 to like I said researchers argue between like 19 and 21 so it can go all the way up to 21 Okay, so now let's talk about some of the kind of risky behaviors the teens engage in again Just keeping in mind like you put all these things together I just said and it makes sense that adolescents maybe don't always make the most amazing great decisions I made all kinds of terrible decisions during this age range for sure So adolescents engage in lots of risky sexual behaviors. About 70% of teens report that they have had sex by the age of 19. You know, obviously hormonal changes are going to lead to increased sex drive and then, you know, all the things I talked about makes it so that teens are not considering the risks of that and they're only weighing the rewards and focusing heavily on that. We also get all kinds of messages from the media that make it seem like sex is risk-free. You know, you see sexual things happening in movies, and they're not often concerned about protection or birth control or condoms, and it doesn't often depict, you know, the negative outcomes that can come from that. So it often leads adolescents to think, like, you know, this is a completely unrisky behavior to engage in. And then in addition to that, I would say the sexual education in this country is pretty lacking, especially in more, like, rural conservative areas. And so a lot of teens are just misinformed or uninformed about the possible consequences and how to avoid them. Maybe not surprisingly, authoritative parents who have, you know, that warm bond with their children, they're much more likely to have conversations about sex and so their children are less likely to have negative outcomes from sexual behaviors. They're not less likely to have sex, but they are more likely to use protection. and to make decisions that will help guard against the negative outcomes. Yeah? That's something I've never really understood why people get so, like, up in arms, you know, teenagers having sex. Teenagers have had sex since the dawn of time. Yes, yeah. That's what I, it's not anything new. Right, yeah. I, yeah, I agree. It's crazy. I'm like, oh, that's so immoral and wrong and how dare you. I'm so shocked and surprised. Right, yeah. Really? Yeah. I would guess this is mostly religious reasons and that prior to pretty recently most people would have been married by like 14 or 15. But still, it's kind of still the same. Yeah. Yes. So in addition to 70% having sex by the age of 19, about 14% report that they do not use contraception consistently. Keep in mind these numbers are from self-reports. which means that everything you see here in reality is probably much higher because there are obviously going to be teens who, even in an anonymous self-report, are not going to want to say that they've had sex, even if they had. They're not going to want to say that they're not using contraception. So, yeah. So about 20% of sexually active teens will get an STI or an STD, that's sexually transmitted infection or disease. And there's about 750,000 teen pregnancies per year. Also, all these numbers, I think they come from, like, probably like 2010 or so. So there might've been shifts in these numbers. I would imagine in general, they were trending up. COVID probably caused a decrease in a lot of this just because the opportunities would have lessened. But then I would imagine it's probably upticking again. All right, let's see. So, you know, full disclosure, I got pregnant when I was 19. So I would have been in this adolescent. age range. But I just want to tell you a little bit about outcomes of teenage pregnancies, which are probably not surprising to you. So about one in four teenage pregnancies end in abortion. So much more likely to get an abortion if you have an unplanned pregnancy in adolescence. About 90% of those teenage pregnancies are going to happen outside of marriage. Typically, girls who come from low socioeconomic status Girls who come from divorced parents, have poor school achievement, those are gonna be the ones that are more likely to have a pregnancy during this this age range. And then often both the mother and the child from the teenage pregnancy will have negative outcomes. So girls who get pregnant are much less likely to graduate from high school, less likely to go on to higher education, they're more likely to have more unplanned pregnancies after the first one. They're likely to be a single parent and to have difficulty having healthy, strong relationships going forward. And they also tend to have financial difficulties, and they typically might have weaker parenting skills. So they're more likely to fall into either the authoritarian or the permissive parenting style instead of using that authoritative parenting style that we've talked about multiple times. So that's generally what happened. Yeah, Valerie, you're good. I watched a documentary a long time ago on child marriages in the U.S. and I had no idea that they are still, like, legal, even below what you would expect to be, like, maybe okay. Right. And it was just, like, all the testimonies of the women who were forced to marry, like, men who had molested them as children. And then they get pregnant, you know. Yeah. And then they have to be married. There was a woman who got married at, like, 11. And she has like eight children. Oh my goodness, that's crazy. I know. Yeah, I mean I knew, I know in some states that I was aware of, the lowest age was like 14. But even that. Yeah. I guess it's still happening though. Yeah. Yeah. Let's see. When they get stuck in a marriage like that, they can't get out. They can't like file for divorce because they're not legal adults yet either. right yeah yeah I have to look into that maybe add some stuff about it in future classes I didn't realize it was legal that young right I might have right yeah yeah Okay, so in addition to risky sexual behaviors, adolescents are also pretty likely to engage in substance use in really risky ways. So again, we've got statistics here. 50% of teenagers report using at least one drug. 62% have abused alcohol, meaning that they used it to get, you know, like drunk. The earlier, in general, the earlier that you use a substance, the more likely it is that you will become addicted to it because the brain is still developing, particularly that reward network that I talked about earlier. It's the reward network that gets kind of miswired is what leads to addiction. And so if you use a substance while that area is still in development. Then you're much more likely to develop an addiction from that so that's one of the biggest risks of using drugs at this age is the development of an addiction Yeah, so use of substances can often lead to poor decisions You know people who are drunk or on a substance are less likely to make good decisions because it tends to inhibit the prefrontal cortex They also tend to have decrease academic performance, and increased risk of other psychological disorders, particularly if one of the safer drugs to use, maybe, is marijuana. That's what we often, you know, that's going to be safer than alcohol or cocaine or other drugs. But even so, someone who uses marijuana, particularly chronically or in this early age, is more likely to develop schizophrenia and other types of psychological disorders. Are those supposed to be good for your brain? I'm... So yeah, I would say using any substance in this early age period is pretty dangerous. Once you get into adulthood, some of them might be safer. But yeah, in adolescence, your brain is still forming. Much more risky to use it then. Do you think that there's a correlation between higher use of marijuana? And developing schizophrenia? Yes. Yeah. Yeah. And there's some, I mean, there's some research that suggests a causal mechanism there. There's something about the way the brain affects, or the way that marijuana affects the brain. Like, triggers it? Yeah. Might trigger. Especially if you already have other risk factors to develop schizophrenia, that might be the thing that, like, pushes you over the edge. Yeah. In your opinion, would you feel like the effects or, like... Is the chance of effects of insomnia worse than, say, the other? You're asking, is the effects of insomnia worse than this? The one or the other. Right. That's difficult to say. I mean, I think if we're looking at short-term side effects, probably, yeah. Like, insomnia might be worse. But if you think about the long-term possibility of addiction. then that would tip me over to saying that maybe drug use would be more dangerous. But yeah, insomnia and chronic sleep deprivation is extremely dangerous, extremely negative on the way that it impacts brain development. So I would say they're probably more equal than most people would think they are. I'm pretty sure that's what killed Michael Jackson, taking him to sleep and so he kept taking more and more of his sleep in. We never thought of it that way. I'd be lying if we just used weed. This whole class, just a PSA for a week. All right, so let's move on from risky behaviors to talking a little bit about cognitive development. So let's first look through Piaget's lens. So according to Piaget, adolescents are entering what's called the formal operational stage. So some of the skills they've developed at this time, one is hypothetical or deductive reasoning. So this is, you know... problem solving based on a hypothesis, where you form a hypothesis and then you test that through variables, etc. That all sounds very like scientific and formal, formal is even in the name, but we do this in a lot of ways without even realizing it, in kind of more informal settings. So, you know, I might develop a hypothesis that my crush likes me, and I might test that hypothesis by texting them something suggestive or you know, so hypothesis testing doesn't have to mean science necessarily It's just there. They're using that type of thinking to come to decisions to understand information, etc Yes, yeah I'd say another part of this though is that they're able to consider multiple variables at a time and try to figure out like which variable is going to be most impactful. I always like throwing like questions or topics. Right, yeah, you're just collecting your data until you can come to a valid conclusion. Yeah, yes, we do this all the time without realizing it. They also are becoming better at propositional thought, so that's the ability to evaluate more like verbal, abstract, non-tangible things. So according to Piaget, it's not universal that everyone gets to this stage. So this is the fourth stage, right? We're in the final stage of Piaget. So yeah, so according to Piaget, this is like the final stage of cognitive development, but there's pretty good evidence that not everyone gets here. So some people might be stuck in the previous stage basically forever. I think my mom would be stuck in the previous stage forever. She never went beyond addition and subtraction in math. Yeah. Yeah. My mom is probably similar. She dropped out of high school when she was 16, and that would have been in like the early 70s or late 70s or something like that. Yeah, late 70s. Probably, yeah. So she probably would have. been and I would assume if she had dropped out of high school she probably wasn't in the highest math available at that time so yeah it makes you wonder you know and then like when they start telling you things it's like well you never took any history classes in high school like how do you how do you know yeah I mean, to be fair, there's lots of ways to learn outside of school, but... Okay, so kind of broadening out from Piaget and just talking about cognitive developments in more general terms. I mean, we already kind of talked about scientific reasoning. That would fit in with the hypothesis testing we were talking about. Let's see. Some of the stuff on here is more limitation-focused rather than the strengths. So adolescents in general tend to be highly self-focused. This is, again, common across generations, too. I feel like this is something that older generations like to point out right now about teenagers, but, like, this has been true about teenagers forever. We have other terms for it now, maybe. So, like, main character syndrome is kind of the idea of self-focusing, like this idea that the world revolves around you, that you're the main character, that you're the most important, et cetera. A lot of teens... What's that? we all are is the thing you are but also i am and everyone else is too um yeah it's funny like my son has been calling me an npc as an insult now oh my god when I do anything that he thinks is not interesting or whatever. He's such an NPC. We talked about dressing up as NPCs for Halloween. And if we had neighbors close enough, maybe stage it where we just T-pose for a long time as we pass by the window. And then when they press the doorbell, then we get into character. And he's like, I can't believe it's Halloween. What? Now can we marry? Yes, yeah, it would. I would love it. Yeah, so they tend to see themselves as kind of the center of the universe. They also tend to have very idyllic views of the world. They often get into the state of feeling like they know everything, kind of. Have you all heard of the Dunning-Kruger effect? It's basically this idea that as soon as you learn a little bit about something, you tend to think that you're an expert in that field. true experts tend to realize that there's like a massive, vast amount of information that they don't know and will never know. So people who know just a little bit tend to be way more confident in their knowledge than people who know a lot about something. And I feel like teenagers are kind of just walking Dunning-Kruger effects, like they're getting into high school, they're starting to learn a little bit about politics and history and all this stuff. And as soon as they learn a little bit, they feel like, oh my gosh, I know everything about the world. I'm so smart. And so then they have very idealistic, rigid beliefs about those things, about politics, about religion, about history, etc. And you're kind of unwavering a little bit. And that will change, we will see, as you get into, you know, later into adulthood. So the one Taylor Swift song I do really like, only because she does it with Phoebe Bridgers, who I love. What is the lyric? It's like, how could I know? Oh my gosh, I'm going to blank. it now. It's like how could I how could I know everything at 18 but nothing at 22 I think is the lyric something like that very much in line with this that when you're a teenager you think you know everything And then all of a sudden, especially people who go to college and interact with people from other cultures and start to broaden their perspectives, they have this moment of realizing, oh my gosh, I don't know anything. And then the fun part is around 30, you realize, like, wait, nobody knows anything. Nobody knows what they're doing. So yeah. That's true. Yes. As we already kind of talked about, adolescents also tend to focus a lot on immediate rewards. They're a little bit less great at thinking about long-term effects and consequences. And then in terms of cognitive developments, we see some gender differences and mental abilities start to emerge around this time that I want to talk about a little bit. The biggest gender difference that has been consistently found in terms of cognitive development is that boys tend to have better spatial reasoning and girls tend to have better verbal reasoning. So spatial reasoning is understanding like the spatial nature of something. So the way that they test spatial reasoning, there's, I mean, there's a lot of ways, but one of them, they will give like a, like some sort of drawing of like a three dimensional kind of like Tetris-y looking thing, say like that. Okay, so you'll get this, and then there will be a bunch of kind of similar images of this rotated in different directions. Except only one of them will actually be this thing rotated, right? And the rest will be kind of similar and you have to just look at it and decide like which one is this same thing but rotated. There's another one they do kind of similar to that. Maybe I can just use this drawing. Would that work? I don't know. So they would draw something like this and say imagine that this is a box that's been like cut and unfolded and you're gonna fold it back up into a cube and then they'll put like two arrows. And they'll say, okay, if you folded it up, would those arrows meet? So it's like you're taking something, you know, visual and in your mind, trying to spatially manipulate it and figure out how it'll go together or whatever. So that's how they tend to measure the spatial reasoning, which, again, boys tend to be better at. And then verbal reasoning is things like, you know, if you've taken like the ACT, the verbal component of that would be a good example of verbal reasoning. Or they have SAT out here, not ACT. But yeah, do they even do that anymore too? Do they stop doing that during COVID? So I don't know if you guys even take like standardized testing. No. Okay. I need to find another example now. It's crazy to me. I read somewhere that men and boys tend to be more interested in things and objects and women tend to be more interested in people. Yeah. I think that's in terms of like conversations with other people that they have. Those are the topics that tend to come up. their priorities and like their interests and things you know i was just talking to my husband about that too and it's like i like this subject because it helps people or because i get to learn about people you know yeah whereas like if you know a man who's more interested in things might be more interested in like the theories of development or like the, you know, brain chemistry behind it or something. Right. That's interesting. Were you saying something, Ashley? I was just saying the waffle. Like, it's like the SOT. Okay. Yeah. Yes. So, yeah, like verbal, so whenever. I took the ACT like forever ago. It would have like analogies and synonyms and stuff like, you know, yeah, just verbal things basically. So the interesting thing though is that there's pretty good evidence that a lot of that comes from more like societal and cultural factors than it does from biology. So they did a study, for example, where they tested men and women on their spatial abilities using a test like the one I just described. Then they had them play, so half of them, half of the men and half of the women. played a very spatial video game for six weeks, like an hour each day for six weeks or something like that. So it was some sort of video game that involved navigating a map in order to find something, so lots of spatial reasoning to play it. So half of the men and women played that game, the other half played some other video game that had no spatial reasoning behind it. And then they tested their spatial ability again. They found that both men and women had improved on their spatial ability, but women improved so much more that by the end of it, men and women were equal at their spatial reasoning. So all that suggested that maybe it's just something about, right, historically, men have been more likely, boys have been more likely to play video games than girls. That's changing now, finally, thankfully. But that used to be like a huge stereotype. I, in fact, I think we kind of talked about like Legos. My parents not letting me have Legos. Very same with video games. We had a PlayStation, we had an Xbox at some point. They were always in my brother's room and I was basically never allowed to play them unless my brothers let me, which they never did because I was a little sister and they didn't like me. So yeah, so I never got to play video games even though I really liked them and play them a lot now. So some of those societal things are probably what impact those gender differences and mental abilities and if we... treated genders pretty much the same from childhood, then we almost certainly would not see those differences once you get to adolescence. All right, any questions about physical and cognitive developments in adolescence? Interesting. Right. Yeah. Oh my. Sometimes he does doodle though. He says that helps a lot. Interesting. I don't know if that has something to do with, you know, like, facial reasoning or something. Yeah.

Today we're talking about adolescence. Probably, in my opinion, one of the more interesting time periods to talk about. Very tumultuous time and development as I'm sure you all remember fondly.

So adolescence runs maybe a little bit later than you would think. So it goes from 12 until at least 19 and some researchers even count adolescence up until about like 21 because there's some pretty interesting brain developments happening up until like early 20s. So I would say definitely 12 to 19, maybe up to 21-ish is the age range we're talking about here.

So if we're talking about physical changes in adolescence, you can probably assume that puberty is going to be a huge part of that. So puberty leads to all kinds of really dramatic changes in our physical appearance, and it also impacts the brain in really significant ways that we'll talk about. And then in the next PowerPoint, we'll also talk about how puberty affects our emotions and social interactions.

Because of some of the changes in the brain, adolescents are much more prone than other time periods to engage in some really risky behaviors. So we'll talk a little bit about some of the brain changes that contribute to that. And then we'll also talk about some cognitive developments in things like reasoning abilities and scientific understanding.

So that's the plan for today. So let's start with puberty. So kind of the main thing that's driving a lot of the changes that you experience during puberty are in hormonal changes.

So, you know, all genders have some growth hormones that are contributing to overall physical growth. The main ones are thyroxine, and then there's also a hormone that's literally just called growth hormone. So growth hormone and thyroxine are the two. Biggest hormones that are contributing to just like overall growth where you get another growth spurt around this time around puberty.

And then in addition to those there are also what we call the sex hormones. And sex hormones tend to differ based on gender. So the two biggest groups of sex hormones are androgens and estrogens.

Androgens would include things like testosterone for example is the biggest one. Androgens tend to be more active in cisgender boys and then estrogens are more active in cisgendered girls Although all genders have a little bit of each of those there's like this imbalance between the genders So the androgens again that would be like testosterone they tend to contribute to like hair growth all over the body They contribute to the growth spurts that cis boys experience during this time and particular to the development of muscles and they also increase metabolism and tend to like broaden the shoulders and then the Estrogens that would include estrogen and progesterone are the two big Estrogen sex hormones again. They tend to be more active in cisgendered girls. They're gonna stimulate like growth of the breast tissue They help with maturation of the you know genitals and females vagina.

They also contribute to like fat storage in particular areas. So cis girls tend to, you know, develop fat mostly in like the thighs and the hips. And then importantly those estrogens also trigger the menstrual cycle.

So these hormonal changes are going to contribute to a lot of the primary and secondary sexual characteristics. So primary sexual characteristics are basically the genitals. And then secondary sex characteristics are the things that we can mostly see.

So things that are visible like, you know, largening of the breasts, growth of facial hair, etc. There tend to be pretty large individual differences in the onset of puberty. So it can happen as early as like 9 or 10 in some cases.

And then as late as, you know, 14 or 15. It's a pretty normal range for the start of puberty. And those differences can actually impact the genders in different ways. So there's pretty good evidence that girls who are early bloomers, like girls who have puberty earlier, tend to have worse outcomes than girls who are late bloomers.

So girls who are early bloomers, they tend to have issues with like self-esteem and self-confidence. They tend to be much more uncomfortable physically in their body. They also tend to be like bullied and ostracized more.

For boys, it's basically the opposite. So boys who tend to be early bloomers if they start puberty earlier They're gonna grow to a taller height sooner. They're gonna, you know build up muscle sooner And so they tend to have better social outcomes compared to boys who tend to be late bloomers So you have a boy that hasn't gone through puberty until fairly late then they're much more likely to be ostracized or bullied Also, kind of interesting note, age of puberty onset has been decreasing for some reason since the early 1900s.

Like overall as a whole population, we tend to start puberty earlier now compared to then. Part of that might actually be a healthy thing. So in the early 1900s, more people were more likely to be suffering from like malnutrition.

And we know that things like malnutrition can actually delay the onset of puberty. So that might be part of that reason for puberty onset. age decreasing now because we have much more access to you know better health outcomes better nutrition etc another thing I want to talk about a little bit really quickly is the use of puberty blockers during this age it's kind of a controversial subject for some people but puberty blockers are usually used they're used for a lot of context but the part that's controversial is when they're used for someone who's transitioning from their birth gender to their gender identity And basically what puberty blockers do, I mean it's in the name, they're like a medication you take that basically stops the hormones, the sex hormones, from being produced as much. And so it will temporarily stop puberty. So it'll stop a lot of the processes that we just talked about.

Someone who takes puberty blockers, they can basically stop taking them at any point and then their puberty would resume just like normal, like it would have if they had never stopped or started taking the puberty blockers. So kind of the idea is that like let's say for example you have someone who's born a female and they want to transition to male Whenever they start to go through puberty their body's going to start pumping out all these estrogens that might start to cause you know breast Growth etc. And if they want to transition to male they identify as male that's going to make them extremely uncomfortable likely So these puberty blockers would stop that process. It would basically shut down the body pumping out that estrogen So they would kind of remain in this like pre-puberty state for a little bit. Some people choose to do that basically to delay puberty so that they have more time to make decisions.

So if it's you know, most the time if someone's transitioning, they're pretty much 100% certain that's what they want to do. But if for some reason they're a little bit on the fence, they think they want to transition, they're not really sure, then those puberty blockers kind of stop them from developing these sexual characteristics for a little bit. So they have more time to think about it and decide. Yeah, Ashley. Yeah, that would be a part of that.

So puberty blockers basically would stop that sexual maturation process. And then most people, the huge majority of people, if they are transitioning and they take the puberty blockers, then they will eventually follow that up by doing hormone replacement therapy or hormone replacement therapy using... the sex hormone of the gender they're trying to transition to.

Right? So again, if you have someone who's born female but they want to transition to male, they might take the puberty blockers to stop the growth of breasts and all of that and then eventually they'll take the testosterone in order to basically start developing like male sexual characteristics. Yeah? Is it one of the drugs, I forget the name of it, but wasn't it used to like chemically castrate offenders?

I don't know. I've never heard that. But that would, I mean, I could imagine that if, like, for example, if there's one that blocks testosterone, if you took it in a high enough dose, then it might, yeah, stop the production of testosterone, which would shut down sperm production.

So that's possible. I've never heard that, though. I mean, shutting down any production is going to kill someone's sex drive. Yeah.

I think no matter what. Right. Yeah. Yeah, it's possible. I mean, they say it doesn't happen on, like, hormonal birth control, but it totally does.

Yeah, definitely. Yeah, there's all kinds of effects of hormonal birth control that are not taken as seriously as they should be, probably. Essentially, so yeah, so if you have, let's see, the opposite, right? You have someone who's born male, they want to transition to female, then they would take the puberty blockers, and then later on they would supplement with estrogens, which would be, yes. Yeah, yeah, so yeah.

birth control would have very similar effects and would fall in the same kind of category. So some of the controversy or the criticisms of puberty blockers, one is fairly valid, which is that puberty blockers tend to decrease bone density. So another thing that these sexual hormones do is that they help strengthen and grow the bones.

And so if you're blocking... The, you know, puberty, if you're blocking those hormones during puberty, even if someone then starts taking the hormone supplements later or they stop taking puberty blockers, they still aren't going to develop the same bone density as someone who's just allowed to go through puberty naturally. Yeah.

Does it affect long-term fertility? I would imagine so. I haven't, I don't remember reading that directly, but yeah, I would imagine that it probably would. Yeah, so there are side effects, but I mean obviously there's side effects to all kinds of medications and people make decisions based on mitigating risk and weighing benefits, etc.

Another common criticism you hear that's much less valid is the concern that, you know, what if someone changes their mind? So kind of the idea is that if you have someone who's 12, you know, are they able to make a lifelong decision that they're not going to regret? And if they do take these puberty blockers and start transitioning and then they get to 18 and they decide like oh This was a bad choice, then you know that might have negative outcomes However, you know statistically about 99% of people who choose to take puberty blockers are happy with that decision in adulthood 98% of them will go on to do other transitional therapies, so if they start taking the puberty blockers It's very very high chance that they will follow through with the hormone replacement therapy, and in a lot of cases also might follow through with, like, surgeries. Yeah? I heard of this other study.

It was a long time ago, and I can't remember the name of the guy, but I think he was Canadian. And he did a, I think it was a longitudinal study on adolescents who had gender dysphoria. Yep. I feel like crap that I can't even, I didn't remember the name of it, but he said that a majority of the children that he studied ended up by the age of 18 just detransitioning, I suppose.

I think he ended up like losing his license for it. Interesting. Yeah. Yeah.

Canadian. You know, he chose his Canadians. Right, yeah. Yeah, I mean most of the studies I've read, like I said, say that 99% of the children are Canadian. of them end up being happy with it.

Yeah, that's what I'm wondering. Maybe in that particular case, he was pressuring people to do it or something for some reason. I mean, who knows? Yeah, and also just to put that into context, so if 99% are happy with it, with it, that means about 1% end up regretting the decision.

About 1.2% of people regret getting LASIK eye surgery because it has long-term side effects, can have dry eyes and stuff. So pretty much any medical procedure you can think of, of course, there's going to be people who end up regretting doing that procedure because there's complications or things that they didn't think through. So that's often one of the arguments that's used to say we shouldn't let people use puberty blockers.

In my opinion, it's not a very great argument against. So kind of like I think we talked about this last time, this idea that if you have someone in late childhood who's expressing, you know, wanting to transition, then it's good to support that. Same thing here in general if an adolescent someone is wanting to transition genders, all the evidence suggests that the best outcomes are going to come from supporting that decision.

And if they're not supported, that can often lead to you know, depression, anxiety, suicidal thoughts and tendencies. So really negative outcomes if you don't try to accept their transition. Yeah? I also read somewhere that it's like a really astronomical number of people who are transitioning or have transitioned that they have like an attempted suicide rate that's really high too.

Yeah. It seems like it's just being all around. Yeah, I would imagine that being in that transitionary phase is probably the most difficult part, right? Because you're...

I'm sure most people are very uncomfortable in the body of their born gender, but then being in that transition, you're kind of like halfway in between and not really comfortable. But then people who go through the full transition and come out the other side tend to have much better outcomes. All right, so I've got to say about puberty for now.

We might talk about it a little bit more in the context of emotional and social development. Well, it's not all I have to say about it. It's all I have to say about the sexual changes from puberty, at least.

Puberty... contributes pretty significantly to some drastic changes in brain development. So a couple things to note, up until early 20s the prefrontal cortex is still not fully developed. So even for some of you in this classroom, you know, depending on your age you might not have a fully developed prefrontal cortex yet.

And that is the part of the brain that's involved in executive control, which we've talked about multiple times, you know, that ability to plan, set goals, self-regulate, etc. So that won't be fully developed, like I said, until about early 20s. Most of the development that's going on physically is myelination and pruning.

So you've got pretty much all the neurons in place at that point, but the myelin is not fully developed. And again, myelin is the part that sort of speeds up those connections in the brain. So during adolescence, you're still having some of that development happening.

Prefrontal cortex is continuing to develop. So executive control is getting better, but it's still not at its peak that it will be in early 20s. Maybe more importantly, there's also some pretty drastic changes going on in the reward network of the brain.

So the reward network is a system of structures that is active whenever we do something pleasurable, basically. So this would involve like dopamine. If you've ever heard of dopamine, this whole idea of, you know, lots of things that are addictive tend to trigger dopamine activity.

That's the neurotransmitter that's used in this particular network. And in adolescence, there are some really interesting things happening in that network that basically make it so that adolescents, when they're making a decision, they tend to weigh the rewards of an outcome way more. And they tend to discount the risks or the possible, you know, negative outcomes of that decision.

So if you have a teenager who's, you know, with their friends and their friends are asking them to drink or use drugs or whatever, and they're making a decision about whether or not to do that, they're going to focus a lot on the reward. They're going to focus on, OK, this is going to be fun. It's going to feel good.

My friends are going to think I'm cool, et cetera. And they're not going to think about the possible negative consequences of that because of like literal. neurological, physical changes in the brain that kind of make them think that way, basically. So we're going to talk a little bit about risky behaviors that teenagers engage in. And I guess kind of the main thing I want you to think about now is that that's completely normal and sort of built into our brains to act that way during adolescence.

So in addition, I mean, I kind of, this is more relates to... the prefrontal cortex stuff I was talking about, you've also got some synaptic pruning still going on in some areas and expansion in the others. So, you know, expansion is mostly happening in the prefrontal cortex.

So yeah, so continued changes in brain development, basically. All right, some other physical changes that are happening in adolescents have to do with the sleep-wake cycle. And again, this is... partially due to changes in the brain and also changes in those hormones that we've already talked about. And those changes sort of combine to lead to later sleep onset and also to the need for more sleep compared to early and middle childhood.

So in an ideal setting, adolescents would basically be allowed to go to sleep later and sleep for longer than they did in childhood. Unfortunately our society isn't really set up to support that although there are some initiatives to try to change that. So in the past decade or so I've seen all kinds of states trying to implement rules for like you know starting high schools later and setting rules about how early they can start and having like thresholds on that. So yeah so but because of these changes and sort of come yeah go ahead Valerie. her kid being on an opposite schedule was a really big pain in the ass to her.

And there was no other way to get, I think it was pre-COVID too, so there wasn't like online classes there. But it was a big pain in the ass and it made me think about that. Like there are a lot of adults who are on a nighttime schedule.

It's just not, I don't know. My husband was on the night schedule for a long time, you know, in the military. It was rough. Yeah, yeah, it's very, yeah, yeah, definitely. It's extremely difficult.

And yeah, and I mean, even. you know, outside of that, like I'm saying, like pretty much all of society is set up to run from nine to five or whatever. And our school systems run mostly from, you know, eight to three-ish. And yeah, it's just not really conducive to the development of adolescence. So yeah, so because of that, adolescents are chronically sleepy, basically, as I'm sure all of you are aware and probably feeling right this moment.

And lack of sleep leads to all kinds of negative outcomes. It impairs executive function, which is already not... fully developed, so then that's going to contribute, again, to some of those risky behaviors.

Impaired emotional regulation, also reduced achievement in school, increased anxiety and depression, and then all of that sort of combines to some of the high-risk behaviors we'll talk about in a little bit. Also, I should point out, too, that lack of sleep has all kinds of physical negative outcomes. It can reduce our immune function, so we're more likely to get sick.

It also has really negative impacts on the brain if you're not sleeping enough or sleeping deeply enough There's pretty good evidence that chronic lack of sleep might increase your risk for Alzheimer's and dementia Partially because so while you're sleeping your brain is actually flushing a lot of like waste material And if you're not getting enough sleep, then you're not going through that process and those waste materials sort of build up and cause declines in the neurons, basically, that can lead to, like I said, Alzheimer's and dementia. So it's a really important issue. Does it have any effect on the physical growth, too? Because that's... Yes, yeah, I mean, that's another thing that's happening while you're sleeping.

Your body's repairing, recovering from exercise or any other sort of damage, and also, yeah, contributing to growth. So, yeah, lack of sleep is going to impair all of that. Alright, teens also tend to have somewhat poor nutrition compared to some of the other age ranges we've talked about.

And part of that is due to the fact that calorie requirements increase. So when you're going through puberty, you know, all this growth is happening. You know, also high schoolers often very likely to participate in like extracurricular activities, sports and physical education and all of that. So they need more calories, but they often are on a time crunch.

Again, I always feel kind of silly talking about adolescence. It's like my favorite, most interesting time period. But saying all this to all of you who are mostly in adolescence feels so silly to me.

Like, you know this because you're living it every single day. So adolescents tend to be on a pretty big time crunch. They're going to school. They've got extracurriculars.

A lot of people start working during this time period. And so trying to find time to eat even remotely healthy is very difficult. So adolescents are more likely than any other time period to eat on the go. So eating fast food or just grabbing like you know a granola bar or something to eat for breakfast.

In addition to that around this age is when eating disorders become most common particularly in girls. So all of that can lead to poor nutritional outcomes. You've got adolescents whose brains aren't fully developed, not getting enough sleep, they're not eating great. Yeah, did you have a question? So we're talking 12 to like I said researchers argue between like 19 and 21 so it can go all the way up to 21 Okay, so now let's talk about some of the kind of risky behaviors the teens engage in again Just keeping in mind like you put all these things together I just said and it makes sense that adolescents maybe don't always make the most amazing great decisions I made all kinds of terrible decisions during this age range for sure So adolescents engage in lots of risky sexual behaviors.

About 70% of teens report that they have had sex by the age of 19. You know, obviously hormonal changes are going to lead to increased sex drive and then, you know, all the things I talked about makes it so that teens are not considering the risks of that and they're only weighing the rewards and focusing heavily on that. We also get all kinds of messages from the media that make it seem like sex is risk-free. You know, you see sexual things happening in movies, and they're not often concerned about protection or birth control or condoms, and it doesn't often depict, you know, the negative outcomes that can come from that. So it often leads adolescents to think, like, you know, this is a completely unrisky behavior to engage in.

And then in addition to that, I would say the sexual education in this country is pretty lacking, especially in more, like, rural conservative areas. And so a lot of teens are just misinformed or uninformed about the possible consequences and how to avoid them. Maybe not surprisingly, authoritative parents who have, you know, that warm bond with their children, they're much more likely to have conversations about sex and so their children are less likely to have negative outcomes from sexual behaviors.

They're not less likely to have sex, but they are more likely to use protection. and to make decisions that will help guard against the negative outcomes. Yeah?

That's something I've never really understood why people get so, like, up in arms, you know, teenagers having sex. Teenagers have had sex since the dawn of time. Yes, yeah.

That's what I, it's not anything new. Right, yeah. I, yeah, I agree.

It's crazy. I'm like, oh, that's so immoral and wrong and how dare you. I'm so shocked and surprised.

Right, yeah. Really? Yeah.

I would guess this is mostly religious reasons and that prior to pretty recently most people would have been married by like 14 or 15. But still, it's kind of still the same. Yeah. Yes. So in addition to 70% having sex by the age of 19, about 14% report that they do not use contraception consistently.

Keep in mind these numbers are from self-reports. which means that everything you see here in reality is probably much higher because there are obviously going to be teens who, even in an anonymous self-report, are not going to want to say that they've had sex, even if they had. They're not going to want to say that they're not using contraception.

So, yeah. So about 20% of sexually active teens will get an STI or an STD, that's sexually transmitted infection or disease. And there's about 750,000 teen pregnancies per year. Also, all these numbers, I think they come from, like, probably like 2010 or so.

So there might've been shifts in these numbers. I would imagine in general, they were trending up. COVID probably caused a decrease in a lot of this just because the opportunities would have lessened.

But then I would imagine it's probably upticking again. All right, let's see. So, you know, full disclosure, I got pregnant when I was 19. So I would have been in this adolescent. age range. But I just want to tell you a little bit about outcomes of teenage pregnancies, which are probably not surprising to you.

So about one in four teenage pregnancies end in abortion. So much more likely to get an abortion if you have an unplanned pregnancy in adolescence. About 90% of those teenage pregnancies are going to happen outside of marriage.

Typically, girls who come from low socioeconomic status Girls who come from divorced parents, have poor school achievement, those are gonna be the ones that are more likely to have a pregnancy during this this age range. And then often both the mother and the child from the teenage pregnancy will have negative outcomes. So girls who get pregnant are much less likely to graduate from high school, less likely to go on to higher education, they're more likely to have more unplanned pregnancies after the first one.

They're likely to be a single parent and to have difficulty having healthy, strong relationships going forward. And they also tend to have financial difficulties, and they typically might have weaker parenting skills. So they're more likely to fall into either the authoritarian or the permissive parenting style instead of using that authoritative parenting style that we've talked about multiple times.

So that's generally what happened. Yeah, Valerie, you're good. I watched a documentary a long time ago on child marriages in the U.S. and I had no idea that they are still, like, legal, even below what you would expect to be, like, maybe okay.

Right. And it was just, like, all the testimonies of the women who were forced to marry, like, men who had molested them as children. And then they get pregnant, you know. Yeah.

And then they have to be married. There was a woman who got married at, like, 11. And she has like eight children. Oh my goodness, that's crazy. I know. Yeah, I mean I knew, I know in some states that I was aware of, the lowest age was like 14. But even that.

Yeah. I guess it's still happening though. Yeah.

Yeah. Let's see. When they get stuck in a marriage like that, they can't get out. They can't like file for divorce because they're not legal adults yet either. right yeah yeah I have to look into that maybe add some stuff about it in future classes I didn't realize it was legal that young right I might have right yeah yeah Okay, so in addition to risky sexual behaviors, adolescents are also pretty likely to engage in substance use in really risky ways.

So again, we've got statistics here. 50% of teenagers report using at least one drug. 62% have abused alcohol, meaning that they used it to get, you know, like drunk. The earlier, in general, the earlier that you use a substance, the more likely it is that you will become addicted to it because the brain is still developing, particularly that reward network that I talked about earlier.

It's the reward network that gets kind of miswired is what leads to addiction. And so if you use a substance while that area is still in development. Then you're much more likely to develop an addiction from that so that's one of the biggest risks of using drugs at this age is the development of an addiction Yeah, so use of substances can often lead to poor decisions You know people who are drunk or on a substance are less likely to make good decisions because it tends to inhibit the prefrontal cortex They also tend to have decrease academic performance, and increased risk of other psychological disorders, particularly if one of the safer drugs to use, maybe, is marijuana.

That's what we often, you know, that's going to be safer than alcohol or cocaine or other drugs. But even so, someone who uses marijuana, particularly chronically or in this early age, is more likely to develop schizophrenia and other types of psychological disorders. Are those supposed to be good for your brain? I'm... So yeah, I would say using any substance in this early age period is pretty dangerous.

Once you get into adulthood, some of them might be safer. But yeah, in adolescence, your brain is still forming. Much more risky to use it then.

Do you think that there's a correlation between higher use of marijuana? And developing schizophrenia? Yes. Yeah. Yeah.

And there's some, I mean, there's some research that suggests a causal mechanism there. There's something about the way the brain affects, or the way that marijuana affects the brain. Like, triggers it?

Yeah. Might trigger. Especially if you already have other risk factors to develop schizophrenia, that might be the thing that, like, pushes you over the edge. Yeah. In your opinion, would you feel like the effects or, like...

Is the chance of effects of insomnia worse than, say, the other? You're asking, is the effects of insomnia worse than this? The one or the other. Right. That's difficult to say.

I mean, I think if we're looking at short-term side effects, probably, yeah. Like, insomnia might be worse. But if you think about the long-term possibility of addiction.

then that would tip me over to saying that maybe drug use would be more dangerous. But yeah, insomnia and chronic sleep deprivation is extremely dangerous, extremely negative on the way that it impacts brain development. So I would say they're probably more equal than most people would think they are. I'm pretty sure that's what killed Michael Jackson, taking him to sleep and so he kept taking more and more of his sleep in.

We never thought of it that way. I'd be lying if we just used weed. This whole class, just a PSA for a week. All right, so let's move on from risky behaviors to talking a little bit about cognitive development. So let's first look through Piaget's lens.

So according to Piaget, adolescents are entering what's called the formal operational stage. So some of the skills they've developed at this time, one is hypothetical or deductive reasoning. So this is, you know...

problem solving based on a hypothesis, where you form a hypothesis and then you test that through variables, etc. That all sounds very like scientific and formal, formal is even in the name, but we do this in a lot of ways without even realizing it, in kind of more informal settings. So, you know, I might develop a hypothesis that my crush likes me, and I might test that hypothesis by texting them something suggestive or you know, so hypothesis testing doesn't have to mean science necessarily It's just there. They're using that type of thinking to come to decisions to understand information, etc Yes, yeah I'd say another part of this though is that they're able to consider multiple variables at a time and try to figure out like which variable is going to be most impactful. I always like throwing like questions or topics.

Right, yeah, you're just collecting your data until you can come to a valid conclusion. Yeah, yes, we do this all the time without realizing it. They also are becoming better at propositional thought, so that's the ability to evaluate more like verbal, abstract, non-tangible things.

So according to Piaget, it's not universal that everyone gets to this stage. So this is the fourth stage, right? We're in the final stage of Piaget. So yeah, so according to Piaget, this is like the final stage of cognitive development, but there's pretty good evidence that not everyone gets here. So some people might be stuck in the previous stage basically forever.

I think my mom would be stuck in the previous stage forever. She never went beyond addition and subtraction in math. Yeah.

Yeah. My mom is probably similar. She dropped out of high school when she was 16, and that would have been in like the early 70s or late 70s or something like that. Yeah, late 70s.

Probably, yeah. So she probably would have. been and I would assume if she had dropped out of high school she probably wasn't in the highest math available at that time so yeah it makes you wonder you know and then like when they start telling you things it's like well you never took any history classes in high school like how do you how do you know yeah I mean, to be fair, there's lots of ways to learn outside of school, but...

Okay, so kind of broadening out from Piaget and just talking about cognitive developments in more general terms. I mean, we already kind of talked about scientific reasoning. That would fit in with the hypothesis testing we were talking about. Let's see.

Some of the stuff on here is more limitation-focused rather than the strengths. So adolescents in general tend to be highly self-focused. This is, again, common across generations, too.

I feel like this is something that older generations like to point out right now about teenagers, but, like, this has been true about teenagers forever. We have other terms for it now, maybe. So, like, main character syndrome is kind of the idea of self-focusing, like this idea that the world revolves around you, that you're the main character, that you're the most important, et cetera. A lot of teens...

What's that? we all are is the thing you are but also i am and everyone else is too um yeah it's funny like my son has been calling me an npc as an insult now oh my god when I do anything that he thinks is not interesting or whatever. He's such an NPC.

We talked about dressing up as NPCs for Halloween. And if we had neighbors close enough, maybe stage it where we just T-pose for a long time as we pass by the window. And then when they press the doorbell, then we get into character. And he's like, I can't believe it's Halloween. What?

Now can we marry? Yes, yeah, it would. I would love it. Yeah, so they tend to see themselves as kind of the center of the universe.

They also tend to have very idyllic views of the world. They often get into the state of feeling like they know everything, kind of. Have you all heard of the Dunning-Kruger effect? It's basically this idea that as soon as you learn a little bit about something, you tend to think that you're an expert in that field. true experts tend to realize that there's like a massive, vast amount of information that they don't know and will never know.

So people who know just a little bit tend to be way more confident in their knowledge than people who know a lot about something. And I feel like teenagers are kind of just walking Dunning-Kruger effects, like they're getting into high school, they're starting to learn a little bit about politics and history and all this stuff. And as soon as they learn a little bit, they feel like, oh my gosh, I know everything about the world.

I'm so smart. And so then they have very idealistic, rigid beliefs about those things, about politics, about religion, about history, etc. And you're kind of unwavering a little bit. And that will change, we will see, as you get into, you know, later into adulthood. So the one Taylor Swift song I do really like, only because she does it with Phoebe Bridgers, who I love.

What is the lyric? It's like, how could I know? Oh my gosh, I'm going to blank.

it now. It's like how could I how could I know everything at 18 but nothing at 22 I think is the lyric something like that very much in line with this that when you're a teenager you think you know everything And then all of a sudden, especially people who go to college and interact with people from other cultures and start to broaden their perspectives, they have this moment of realizing, oh my gosh, I don't know anything. And then the fun part is around 30, you realize, like, wait, nobody knows anything.

Nobody knows what they're doing. So yeah. That's true.

Yes. As we already kind of talked about, adolescents also tend to focus a lot on immediate rewards. They're a little bit less great at thinking about long-term effects and consequences. And then in terms of cognitive developments, we see some gender differences and mental abilities start to emerge around this time that I want to talk about a little bit. The biggest gender difference that has been consistently found in terms of cognitive development is that boys tend to have better spatial reasoning and girls tend to have better verbal reasoning.

So spatial reasoning is understanding like the spatial nature of something. So the way that they test spatial reasoning, there's, I mean, there's a lot of ways, but one of them, they will give like a, like some sort of drawing of like a three dimensional kind of like Tetris-y looking thing, say like that. Okay, so you'll get this, and then there will be a bunch of kind of similar images of this rotated in different directions.

Except only one of them will actually be this thing rotated, right? And the rest will be kind of similar and you have to just look at it and decide like which one is this same thing but rotated. There's another one they do kind of similar to that.

Maybe I can just use this drawing. Would that work? I don't know.

So they would draw something like this and say imagine that this is a box that's been like cut and unfolded and you're gonna fold it back up into a cube and then they'll put like two arrows. And they'll say, okay, if you folded it up, would those arrows meet? So it's like you're taking something, you know, visual and in your mind, trying to spatially manipulate it and figure out how it'll go together or whatever.

So that's how they tend to measure the spatial reasoning, which, again, boys tend to be better at. And then verbal reasoning is things like, you know, if you've taken like the ACT, the verbal component of that would be a good example of verbal reasoning. Or they have SAT out here, not ACT. But yeah, do they even do that anymore too?

Do they stop doing that during COVID? So I don't know if you guys even take like standardized testing. No. Okay.

I need to find another example now. It's crazy to me. I read somewhere that men and boys tend to be more interested in things and objects and women tend to be more interested in people.

Yeah. I think that's in terms of like conversations with other people that they have. Those are the topics that tend to come up. their priorities and like their interests and things you know i was just talking to my husband about that too and it's like i like this subject because it helps people or because i get to learn about people you know yeah whereas like if you know a man who's more interested in things might be more interested in like the theories of development or like the, you know, brain chemistry behind it or something.

Right. That's interesting. Were you saying something, Ashley? I was just saying the waffle. Like, it's like the SOT.

Okay. Yeah. Yes. So, yeah, like verbal, so whenever. I took the ACT like forever ago.

It would have like analogies and synonyms and stuff like, you know, yeah, just verbal things basically. So the interesting thing though is that there's pretty good evidence that a lot of that comes from more like societal and cultural factors than it does from biology. So they did a study, for example, where they tested men and women on their spatial abilities using a test like the one I just described. Then they had them play, so half of them, half of the men and half of the women.

played a very spatial video game for six weeks, like an hour each day for six weeks or something like that. So it was some sort of video game that involved navigating a map in order to find something, so lots of spatial reasoning to play it. So half of the men and women played that game, the other half played some other video game that had no spatial reasoning behind it.

And then they tested their spatial ability again. They found that both men and women had improved on their spatial ability, but women improved so much more that by the end of it, men and women were equal at their spatial reasoning. So all that suggested that maybe it's just something about, right, historically, men have been more likely, boys have been more likely to play video games than girls. That's changing now, finally, thankfully. But that used to be like a huge stereotype.

I, in fact, I think we kind of talked about like Legos. My parents not letting me have Legos. Very same with video games.

We had a PlayStation, we had an Xbox at some point. They were always in my brother's room and I was basically never allowed to play them unless my brothers let me, which they never did because I was a little sister and they didn't like me. So yeah, so I never got to play video games even though I really liked them and play them a lot now.

So some of those societal things are probably what impact those gender differences and mental abilities and if we... treated genders pretty much the same from childhood, then we almost certainly would not see those differences once you get to adolescence. All right, any questions about physical and cognitive developments in adolescence? Interesting. Right.

Yeah. Oh my. Sometimes he does doodle though.

He says that helps a lot. Interesting. I don't know if that has something to do with, you know, like, facial reasoning or something. Yeah.

Transcript for:Understanding Adolescence: Changes and Challenges

Transcript for:
Understanding Adolescence: Changes and Challenges